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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352

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Resultados da Pesquisa

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    Coffee protein profiles during fermentation using different yeast inoculation methods
    (Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2020) Bressani, Ana Paula Pereira; Martinez, Silvia Juliana; Vilela, Leonardo de Figueiredo; Dias, Disney Ribeiro; Schwan, Rosane Freitas
    The objective of this work was to evaluate the protein profiles of natural and semidry fermented Coffea arabica, either subjected to treatments with different yeast inoculation methods with starter culture or to na uninoculated control. Saccharomyces cerevisiae CCMA 0543 and Candida parapsilosis CCMA 0544 were separately inoculated into coffee by directly spraying the cherries on a terrace or in buckets, for 16 hours before sun drying. Protein quantification showed a significant difference between the protein profiles of the samples collected after natural dry fermentation. The MALDI-TOF MS analysis generated a list of 96 peaks with different massto- charge ratios (m/z) in the samples collected at the beginning and the end of fermentation. The highest number of peaks in the natural dry coffee was observed at the end of fermentation in the samples inoculated with S. cerevisiae CCMA 0543, in bucket, and in C. parapsilosis CCMA 0544 sprayed on the terrace. However, in the semidry processed coffee, the highest number of peaks was observed in the initial fermentation, with a decrease in the peptide peaks after fermentation. The fermentation with different microorganisms, processing types, and inoculation methods affects m/z profiles, influencing the types of proteins found in coffee.
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    Proteolytic activities of bacteria, yeasts and filamentous fungi isolated from coffee fruit (Coffea arabica L.)
    (Editora da Universidade Estadual de Maringá - EDUEM, 2011-07) Rodarte, Mirian Pereira; Dias, Disney Ribeiro; Vilela, Danielle Marques; Schwan, Rosane Freitas
    One hundred forty-four microorganisms previously isolated from coffee fruit (Coffea arabica) were grown on casein agar to evaluate their proteolytic activities. Fifty percent of filamentous fungi, 52.5% of bacteria and 2.6% of yeasts were able to secrete proteases. Positive isolates were further examined in liquid culture for their protease activities by hydrolysis of casein at different pH values (5.0, 7.0 and 9.0) at 30 o C. Bacillus megaterium, B. subtilis, Enterobacter agglomerans, Kurthia sp, Pseudomonas paucimobilis and Tatumella ptyseos demonstrated the highest proteolytic activities at pH 9.0. One yeast isolate, Citeromyces matritensis, had a proteolytic activity of 2.40 U at pH 5.0. Aspergillus dimorphicus, A. ochraceus, Fusarium moniliforme, F. solani, Penicillium fellutanum and P. waksmanii showed the highest activities. Of the bacterial isolates, the highest enzyme activities were observed in B. subtilis 333 (27.1 U), Tatumella ptyseos (27.0 U) and B. megaterium 817 (26.2 U). Of the filamentous fungi, Aspergillus ochraceus (48.7 U), Fusarium moniliforme 221 (37.5 U) and F. solani 359 (37.4 U) had the highest activities at pH 9.0.